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Telephony, intercoms. Schemes, articles, descriptions

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Telephony, intercoms

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solar modules

Section Alternative energy sources. Solar modules are the main component for building photovoltaic systems (PV systems). They can be made with any output voltage. After the solar cells are selected, they must be soldered. Serial elements are equipped with current-collecting grids for soldering conductors to them. Batteries can be made in any combination. The simplest battery is a chain of series-connected cells. You can connect these chains in parallel, getting the so-called series-parallel connection. In parallel, only chains (lines) with identical voltage can be connected, while their currents, according to Kirchhoff's law, are summed up ... >>

Voltage doubling converter

Section Voltage converters, rectifiers, inverters. In amateur radio designs, there is often a need for several supply voltages, while the power supply produces only one, and reworking it is quite complicated. At low consumption currents, various voltage converters (multipliers) can be used. Many of them are complex and require expensive components. Compact and convenient pulse voltage converters. I propose my version of such a converter based on a simple and very popular type 555 timer integrated circuit (domestic analogue - KR1006VI1). The converter allows you to get two voltages from +5 V: +10 V and -5 V ... >>

Switching regulator with protection, 12,6 volts 1,5 amps

Section Voltage stabilizers. This stabilizer was intended to power the Vesna-205 tape recorder. During testing, almost all the overvoltage at the input was used to maintain the output voltage equal to the specified one. The value of the protection current is completely determined by the value of the resistance R6 ... >>

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Articles on telephony, intercoms

Articles on telephony, intercoms; diagrams of telephony devices, intercoms; descriptions of telephony devices, intercoms: 168 articles



Latest news of science and technology, new electronics:

The speech of sperm whales is similar to that of humans 18.05.2024

In the world of the ocean, where the mysterious and unknown coexists with the studied, sperm whales, with their huge brains, are of particular interest to science. Researchers, working with a huge array of audio recordings collected during the Dominica Sperm Whale Project (DSWP) - more than 8000 recordings, seek to unravel the secrets of their communication and understand the structure and complexity of the language of these mysterious creatures. By studying in detail the recordings of 60 sperm whales in the eastern Caribbean, scientists have revealed surprising features of their communication, revealing the complexity of their language. "Our observations indicate that these whales have a highly developed combinatorial communication system, including rubato and ornaments, which indicates their ability to quickly adapt and vary during communication. Despite significant differences in evolution, sperm whales have elements in their communication that are characteristic of human communication," says Shane Gero, a biologist at Carleton University and director of the CETI project. Issl ... >>

Electron spin for quantum information transfer 18.05.2024

The transfer of quantum information remains one of the key tasks of modern science. Recent advances in the use of electron spin to expand the capabilities of information transfer in quantum systems have become very important. Researchers at Lawrence Berkeley National Laboratory are pushing the frontiers of quantum information science by experimenting with the possibilities of electron spin. Electron spin, a natural quantum bit, is a potentially powerful means for storing and transmitting information in quantum systems. Magnon wave packets, collective excitations of electron spin, have revealed their potential to transmit quantum information over significant distances. The work of Berkeley Lab researchers has revolutionized the way such excitations propagate in antiferromagnets, opening up new prospects for quantum technologies. Using pairs of laser pulses, scientists disrupted antiferromagnetic order in one place and simultaneously studied it in another, creating ... >>

Sound-absorbing silk 17.05.2024

In a world where noise is becoming increasingly intrusive, the emergence of innovative materials that can reduce its impact is of great interest. MIT researchers have unveiled a new sound-absorbing silk fabric that promises to revolutionize quiet spaces. The Massachusetts Institute of Technology (MIT) has made significant breakthroughs in the field of sound absorption. Researchers have developed a special silk fabric that can effectively absorb sound and create cozy, quiet environments. The fabric, thinner than a human hair, contains a unique vibrating fiber that is activated when voltage is applied to it. This feature allows the fabric to be used to suppress sound waves in two different ways. The first method uses fabric vibrations to generate sound waves that cover and cancel out unwanted noise, similar to noise-canceling headphones. This p ... >>

Random news from the Archive

Liver stones and sports 14.04.2000

Exercising two to three hours a week reduces the chance that you will need surgery to remove a gallbladder full of stones by 20 percent.

The medical records of more than 60 employees of American hospitals and clinics, mainly service personnel, were studied (from these people, who are always "at hand" with doctors, it is easier to obtain both consent to the examination and all the necessary information about lifestyle).

It turned out that among those who had to remove the gallbladder (and there were 3257 people), leading a sedentary lifestyle prevailed. Moreover, in order to avoid an operation, it is not necessary to seriously engage in physical education and sports, it is enough, for example, to walk 2-3 hours a week.

So far, there is no indisputable explanation for this dependence, but it is assumed that active muscle movements prevent stagnation of bile in the bladder, and hence the formation of stones.

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